Ball joints generally comprise a stud which includes a shank and a ball end, and a housing in which the ball end is seated. The ball joint permits the ball end and shank to rotate about the stud axis, as well as to swing or pivot with respect to the stud axis. The housing usually contains a pair of bearings. The bearings have spherical surfaces and ar positioned within the housing in axially opposed relationship to provide bearing surfaces against which the surface of the ball end of the stud can slide. A spring biases one of the bearings against the ball end of the stud to hold the ball end firmly between bearings.
In order to minimize production costs, there are usually tolerances which produce clearances between the outside of the bearings and an inner side surface of the housing which encloses the ball end of the stud. A bearing is normally molded with a slot through one side of the bearing to enable the bearing to be firmly pressed against the ball stud. The presence of the slot allows the bearing to spread open and makes it impossible to consistently control the size of the outside diameter of the as molded bearing. This results in the bearings having random oversize conditions which can cause assembly problems.